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Lactobacillus casei BL23 carries 17 two-component signal transduction systems. Insertional mutations were introduced into each gene encoding the cognate response regulators, and their effects on growth under different conditions were assayed. Inactivation of systems TC01, TC06, and TC12 (LCABL_02080-LCABL_02090, LCABL_12050-LCABL_12060, and LCABL_19600-LCABL_19610, respectively) led to major growth defects under the conditions assayed.

This article is a brief report of the historical data based elaboration processes which contains all Costa Rica´s real state transactions during the first half of 19th century. It explains the elaboration processes step by step, the data base structure of "Transacciones inmobiliarias en Costa Rica durante 1800-1850", the methodology, its relevance, contributions and limitations., Este artículo es un breve informe del proceso de elaboración de una base de datos histórica que contempla todas las transacciones de bienes inmuebles durante la Costa Rica de la primera mitad del siglo XIX. En el mismo se explica paso a paso el proceso de elaboración y la estructura de la Base de Datos "Transacciones inmobiliarias en Costa Rica durante 1800-1850", la metodología, su importancia, sus aportes y limitaciones.

Phosphoketolases (XFPs) are glycolytic enzymes present in several organisms belonging to the Eukarya and Bacteria domains. A total of 151 putative xfp genes were detected in 650 complete genomes available in public databases. Elimination of redundant sequences and pseudogenes rendered a final data set of 128 phosphoketolases, which was analyzed by phylogenetic methods. The distribution of xfp genes was uneven in most taxonomic groups, with the exception of the taxonomical division Lactobacillaceae, in which all the species studied harbored a putative xfp gene. Putative xfp genes were also present predominantly in Rhizobiales and Actinobacteria divisions, in which 23 out of 28 genomes and 23 out of 41 genomes contained at least one putative xfp homolog, respectively. Phylogenetic analyses showed clear discordance with the expected order of organismal descent even in groups where xfp is prevalent, such as Lactobacillaceae. The presence of putative paralogs in some organisms cannot account for these discrepancies; instead, these paralogs are most possibly xenologs. The results of the phylogenetic analyses, the distribution of xfp genes and the location of some xfp genes in plasmids are independent pieces of evidence that point to horizontal gene transfer as a major driving force in the evolution of phosphoketolases. Copyright © 2010 S. Karger AG, Basel.

[Background]: Comparative genomic hybridization (CGH) constitutes a powerful tool for identification and characterization of bacterial strains. In this study we have applied this technique for the characterization of a number of Lactobacillus strains isolated from the intestinal content of rats fed with a diet supplemented with sorbitol. [Results]: Phylogenetic analysis based on 16S rRNA gene, recA, pheS, pyrG and tuf sequences identified five bacterial strains isolated from the intestinal content of rats as belonging to the recently described Lactobacillus taiwanensis species. DNA-DNA hybridization experiments confirmed that these five strains are distinct but closely related to Lactobacillus johnsonii and Lactobacillus gasseri. A whole genome DNA microarray designed for the probiotic L. johnsonii strain NCC533 was used for CGH analysis of L. johnsonii ATCC 33200T, L. johnsonii BL261, L. gasseri ATCC 33323T and L. taiwanensis BL263. In these experiments, the fluorescence ratio distributions obtained with L. taiwanensis and L. gasseri showed characteristic inter-species profiles. The percentage of conserved L. johnsonii NCC533 genes was about 83% in the L. johnsonii strains comparisons and decreased to 51% and 47% for L. taiwanensis and L. gasseri, respectively. These results confirmed the separate status of L. taiwanensis from L. johnsonii at the level of species, and also that L. taiwanensis is closer to L. johnsonii than L. gasseri is to L. johnsonii. [Conclusion]: Conventional taxonomic analyses and microarray-based CGH analysis have been used for the identification and characterization of the newly species L. taiwanensis. The microarray-based CGH technology has been shown as a remarkable tool for the identification and fine discrimination between phylogenetically close species, and additionally provided insight into the adaptation of the strain L. taiwanensis BL263 to its ecological niche.

Lactobacillus casei can metabolize L-malic acid via malolactic enzyme (MLF) or malic enzyme (ME). Whereas utilization of L-malic acid via MLF does not support growth, the ME pathway enables L. casei to grow on L-malic acid. In this work we have identified in the genomes of L. casei strains BL23 and ATCC 334 a cluster consisting of two diverging operons, maePE and maeKR, encoding a putative malate transporter (maeP), a ME (maeE) and a two-component (TC) system belonging to the citrate family (maeK and maeR). Homologous clusters were identified in Enterococcus faecalis, Streptococcus agalactiae, Streptococcus pyogenes and Streptococcus uberis. Our results show that ME is essential for L-malic acid utilization in L. casei. Furthermore, deletion of either the gene encoding the histidine kinase or the response regulator of the TC system resulted in the loss of the ability to grow on L-malic acid thus indicating that the cognate TC system regulates and is essential for the expression of ME. Transcriptional analyses showed that expression of maeE is induced in the presence of L-malic acid and repressed by glucose whereas the TC system expression was induced by L-malic acid and was not repressed by glucose. DNase I footprinting analysis showed that MaeR binds specifically to a set of direct repeats (5'-TTATT(A/T)AA-3') in the mae promoter region. The location of the repeats strongly suggests that MaeR activates the expression of the diverging operons maePE and maeKR where the first one is also subjected to carbon catabolite repression.

The feasibility of ing reach the goal of elimination of Tuberculosis in Chile is again discussed. This goal is now a Ministry of Health objective. The intermediate goal, “advanced elimination”, incidence rate of 10 x 100.000 for the year 2010, was designed as, a “Heath Objetive” for the decennium 2000 – 2010. As regards the future perspectives, we analize the obstacles faced in Chile in relation to the possible effects of the new health system structure on the evolution of Tuberculosis in the country. Furthermore, or the possibility of reaching the final goal, will depends on several factors especially related to the growing importance of high risk groups as the total incidence is reduced. It is imperative to develop specific programs for these groups., En este artículo se plantea nuevamente el tema de la factibilidad de lograr el objetivo de eliminación de la Tuberculosis y él, en cierto modo es la continuación de otro artículo presentado hace tres años en esta revista por el mismo autor. El análisis se centra ahora, principalmente, en la revisión de los obstáculos que se han debido superar para proseguir los esfuerzos destinados a alcanzar la meta llamada “de eliminación avanzada”, tasa de incidencia de 10 x 100.000, para el año 2010, previa consideración de las dificultades concretas encontradas una vez superado el “umbral de eliminación”. Se hacen presente las líneas de trabajo técnico del programa para los años que siguen y se insiste en que lo principal es que se mantenga la voluntad política de apoyar el Programa de TBC y que los Directores de los Servicios de Salud asuman la responsabilidad central que les corresponde en la consecución de la meta 2010 que es un Objetivo Sanitario del Ministerio.

[Background] The phosphoenolpyruvate phosphotransferase system (PTS) plays a major role in sugar transport and in the regulation of essential physiological processes in many bacteria. The PTS couples solute transport to its phosphorylation at the expense of phosphoenolpyruvate (PEP) and it consists of general cytoplasmic phosphoryl transfer proteins and specific enzyme II complexes which catalyze the uptake and phosphorylation of solutes. Previous studies have suggested that the evolution of the constituents of the enzyme II complexes has been driven largely by horizontal gene transfer whereas vertical inheritance has been prevalent in the general phosphoryl transfer proteins in some bacterial groups. The aim of this work is to test this hypothesis by studying the evolution of the phosphoryl transfer proteins of the PTS., [Results] We have analyzed the evolutionary history of the PTS phosphoryl transfer chain (PTS-ptc) components in 222 complete genomes by combining phylogenetic methods and analysis of genomic context. Phylogenetic analyses alone were not conclusive for the deepest nodes but when complemented with analyses of genomic context and functional information, the main evolutionary trends of this system could be depicted., [Conclusion] The PTS-ptc evolved in bacteria after the divergence of early lineages such as Aquificales, Thermotogales and Thermus/Deinococcus. The subsequent evolutionary history of the PTS-ptc varied in different bacterial lineages: vertical inheritance and lineage-specific gene losses mainly explain the current situation in Actinobacteria and Firmicutes whereas horizontal gene transfer (HGT) also played a major role in Proteobacteria. Most remarkably, we have identified a HGT event from Firmicutes or Fusobacteria to the last common ancestor of the Enterobacteriaceae, Pasteurellaceae, Shewanellaceae and Vibrionaceae. This transfer led to extensive changes in the metabolic and regulatory networks of these bacteria including the development of a novel carbon catabolite repression system. Hence, this example illustrates that HGT can drive major physiological modifications in bacteria.

This article is the product of descriptive, not experimental, field research, applied to a group of 15 goat producers from Villa Araure, Lara State. The objective is to describe the circuit in the area. The methodology used was an adaptation of a proposal by Martin et al. (1999) using a diagnostic study and strategic analysis identifying the strengths, opportunities, weaknesses and threats to the circuit. The information was collected using an open ended and closed questionnaire and direct and participant observation. In the study, antecedents and general aspects of the circuit were identified. The goat raising tradition, the availability of electricity in the community, excellent external roadways, as well as deficient internal roads and the lack of aqueducts, public health and education services were emphasized. Rainfall is very low and occurs in two annual peaks that determine the scarce pasture resources and the seasonal production. The circuit is important regionally, its local actors being: suppliers of goods to the city of Carora, producers, local buyers and middlemen, transformers, retailers and consumers. The primary byproducts of the circuit are meat, milk (cheese) and manure in growing demand. The main strengths are a result of an opening to change, horizontal coordination, labor and decentralized commercial channels to the extent that the primary weakness identified were adverse climate, deficiency in water resources and the zoological technical management of the herd. As opportunities, the existence of potential markets and the presence of a milk processor in the area were identified as opportunities, while the desertification, the lack of concrete and effective area policies, goat rustling, and the flight of laborers from the countryside were the main threats, Cet article vise à l'étude du circuit de production chevrière dans le secteur de Villa de Araure, état de Lara, Venezuela. Le travail a été fait à partir d'une recherche de terrain non expérimentale qui a été appliqué à 15 producteurs de la zone avant citée. La méthode employée constitue une adaptation de la proposition de Martin et al (1999) : dans ce contexte, nous avons réalisé une étude diagnostique et l'analyse stratégique des forces, des faiblesses, des opportunités et des menaces du circuit. L'information a été obtenue par le milieu d'une enquête contenant des questions ouvertes et fermées, ainsi que de l'observation directe et participative. Le circuit possède une importance essentiellement régionale. Les acteurs principaux sont les fournisseurs des intrants de la citée de Carora ; les acheteurs locaux et les intermédiaires ; les transformateurs ; les détaillants et, finalement, les consommateurs. Les principaux produits du circuit sont la viande, le lait, le fromage et le fumier de chèvre. Les principales forces trouvées sont l'ouverture des producteurs aux changements, la coordination horizontale, l'expérience de la main d'¿uvre et l'existence de canaux de commercialisation décentralisés. Les faiblesses plus importantes sont la climatologie adverse, le déficit d'eau et le système d'aménagement du troupeau. Les opportunités identifiées sont l'existence de marchés potentiels et la présence d'une industrie pour la transformation laitière dans la zone. Les menaces les plus notoires sont la désertification ; le manque de politiques sectorielles ; le vol des animaux et l'exode des paysans, Este artículo es producto de una investigación de campo, del tipo descriptivo y no experimental, aplicada a un grupo de 15 productores caprinos del sector Villa Araure, estado Lara, con el objetivo de caracterizar el circuito en la zona. La metodología empleada fue una adaptación de la propuesta por Martin et al. (1999), mediante un estudio diagnóstico y el análisis estratégico a través de la identificación de las fortalezas, oportunidades, debilidades y amenazas del circuito. La información fue recolectada a través de una encuesta con preguntas abiertas y cerradas y observación directa y participativa. En el estudio se identificaron antecedentes y aspectos generales del circuito, destacando el arraigo de la cría caprina, la dotación de la comunidad del servicio electricidad, excelentes vías de acceso externas, así como deficientes vías internas e inexistencia de acueductos y servicios de salud y educación. La precipitación es muy baja y se distribuye en dos picos lluviosos anuales que determinan recursos forrajeros escasos y la estacionalidad de la producción. El circuito posee una importancia básicamente regional, siendo sus actores: proveedores de insumos de la ciudad de Carora, productores, compradores locales o intermediarios, transformadores, detallistas y consumidores. Los principales derivados del circuito son carne, leche (queso) y estiércol, de creciente demanda. Sus principales fortalezas resultaron ser la apertura al cambio, coordinación horizontal, la mano de obra y los canales de comercialización descentralizados, en tanto se identificaron como principales debilidades la climatología adversa, las deficiencias del recurso hídrico y el manejo zootécnico del rebaño. Como oportunidades se identificaron la existencia de mercados potenciales y la presencia de una procesadora láctea en la zona, en tanto la desertificación, la falta de políticas sectoriales concretas y efectivas, el abigeato y el éxodo campesino resultaron ser las principales amenazas

The evolution and the present situation of tuberculosis in Chile are described. On this basis, the feasibility of changing from the current “control” program to an “elimination” program, which is now a Ministry of Health objective, is discussed. One of the relevant circumstances considered is the recent configuration, by the Panamerican Health Organization, of a special group of “low prevalence countries”, comprising Cuba, Costa Rica, Uruguay and Chile, which has been entrusted with the task of defining the intermediate targets to be reached on the way to the goal of elimination. As regards the future perspectives an analysis is made of the obstacles faced so far in Chile and in other countries. The last section deals with the possible effects of the current Health Reform on the future evolution of tuberculosis in the country., Se presenta una síntesis de la evolución y de la situación actual de la Tuberculosis en Chile. Sobre esta base, se fundamenta la factibilidad del cambio de programa de “control” a programa de “eliminación”, lo que constituye ahora un objetivo sanitario del Ministerio de Salud. Entre los fundamentos considerados está la constitución por parte de la Organización Panamericana de la Salud de un grupo especial de “países de baja prevalencia” que incluye a Cuba, Uruguay, Costa Rica y Chile, el cual debe definir las metas parciales a cumplir “hacia la eliminación”. En cuanto a las perspectivas, se hace referencia a los obstáculos detectados en diversas experiencias internacionales y a las encontradas en Chile en las etapas cumplidas, para finalizar analizando el eventual impacto de la Reforma de la Salud en la posible evolución de la tuberculosis en el país.

Lactobacillus sakei is a lactic acid bacterium commonly used as a starter culture for dry sausage production and can utilize arginine via the arginine deiminase pathway. The arcABCTD cluster of L. sakei has been characterized, and transcriptional studies have shown that its expression is subject to carbon catabolite repression and induction by arginine. Downstream of arcD an additional gene has been found; this gene, arcR, codes for a putative regulatory protein of the Crp/Fnr family. Transcriptional studies have shown that arcR is coordinately transcribed with the remaining arc genes, and therefore, these genes constitute the arcABCTDR operon. Northern analysis also showed a complex pattern of transcripts, suggesting that processing and partial termination may play a role in regulation of the expression of individual genes of the operon. Inactivation of arcR led to arrest of transcription of the operon, indicating that the ArcR protein is essential for expression of the arc genes. The availability of this mutant made it possible to study whether the ability to utilize arginine affects the growth of L. sakei in meat fermentations. Under our experimental conditions, expression of arginine deiminase does not confer an obvious advantage to L. sakei, since the wild type and an arcR mutant strain displayed similar dynamics of growth.

[ES] En el contexto teórico de la creciente contractualización que tiene lugar entre los agentes económicos de la cadena alimentaria, el objetivo del trabajo es establecer una propuesta metodológica que sirva para caracterizar las relaciones verticales entre la IAA y la DA, enmarcándolas en el proceso de reestructuración del SAA. Para ello, se parte de la elaboración de una fuente primaria de información, a partir de la opinión de los fabricantes, consistente en un «mailing» dirigido al estrato de empresas más dinámico y avanzado tecnológicamente del sector de elaborados cárnicos. Se lleva a cabo una disección de los elementos que componen los acuerdos contractuales entre la IAA y la DA, agrupando los aspectos a analizar del siguiente modo: estrategias comerciales, estrategias organizativas y, a modo de resultados, una evaluación de la capacidad de negociación y una tipología empresarial inherentes a la problemática de competencia vertical de las industrias cárnicas. Entre las principales conclusiones, se detecta que la lógica del predominio contractual de la DM se ha canalizado hasta ahora con mayor intensidad precisamente en el ámbito de los factores de carácter comercial, en un contexto de «confrontación » entre fabricantes y distribuidores. Sin embargo, la presión contractual que la DM está ejerciendo sobre las estrategias comerciales experimenta una cierta tendencia a la saturación y, como consecuencia, comienzan a establecerse estrategias de «colaboración» entre fabricantes y distribuidores en el ámbito de los factores de carácter organizativo, donde destaca el papel central que adquieren las tecnologías de la información., [FR] Dans le contexte théorique de la contractualisation croissante développée entre les agents économiques de la chaîne alimentaire, l’objectif de l’étude vise à établir une proposition méthodologique tendant à définir les relations verticales entre la IAA et la DA, dans le cadre du processus de restructuration du SAA, à partir de l’élaboration d’une source d’informations primaire basée sur l’opinion des fabricants et qui constiste en un «mailing» adressé à un échantillon d’entreprises du secteur des produits a base de viande les plus dynamiques et les plus avancées sur le plan technologique. Il a été procédé à l’examen minutieux des éléments faisant l’objet des accords contractuels entre la IAA et la DA, en les regroupant de la manière suivante: stratégies commerciales, stratégies d’organisation et, à mode de résultats, une évaluation de la capacité de négociation et une typologie patronale relative à la problématique de compétence verticale des industries de produits a base de viande. Parmi les conclusions principales, on observe que la logique de prédominance contractuelle de la DM a été jusqu’à présent largement canalisée précisément en ce qui concerne les facteurs à caractère commercial, dans un contexte de «confrontation » entre les fabricants et les distributeurs. Toutefois, la pression contractuelle exercée par la DM sur les stratégies commerciales souffre d’une certain saturation et, par conséquent, des stratégies de «collaboration» commencent à s’éstablir entre les fabricants et les distributeurs en ce qui concerne les facteurs d’organisation, pour lesquels il faut souligner le rôle essentiel joué par les technologies de l’information., [EN] In the theoretical context of the increasing contractualization that is taking place amongst the economic agent in the food chain, the aim of this paper is to put forward a methodological proposal that will serve to characterize the vertical relations between the AFI and the FD and set them in the framework of the AFS reorganization process. To this end, we start off by compiling a primary source of information on the basis of the opinion of the manufacturers, consisting of a survey aimed at the most dynamic and technologically advanced segment of the processed meat product sector. We analyze the items of the contractual agreements between the AFI and the ED and arrange the aspects to be examined into the following groups: sales strategies, organizational strategies and, by way of results, an assessment of the negotiating power and the business typology inherent in the vertical competition problems of the meat industries. The main conclusions include the fact that the contractual predominance of the WD has hitherto been directed to a greater degree precisely towards the sphere of the sales factors, in a context of «confrontation» between manufacturers and distributors. However, the contractual pressure that the WD has been exerting on the sales strategies is undergoing a certain trend towards saturation. Thus, «cooperation » strategies are beginning to be established between manufacturers and distributors in relation to the factors of an organizational nature, where the most notable feature is the major role being played by the information technology.

[ES] Un rasgo característico de la evolución del sector del aceite de oliva ha sido el escaso nivel de internacionalización de sus intercambios comerciales, que tradicionalmente se han centrado casi en exclusiva en el ámbito de los propios países productores. Sin embargo, en los últimos tiempos se viene perfilando un nuevo escenario de referencia para los agentes económicos que operan en el sector: por una parte, las tendencias de progresiva liberalización del comercio internacional contribuyen a un emergente proceso de globalización de los intercambios internacionales del producto; por otra, las estrategias de los agentes empresariales se encuentran cada vez más influidas por una cadena agroalimentaria crecientemente orientada desde la demanda. Además de estas premisas, que son generalizables al conjunto del Sistema Agroalimentario, nos encontramos con otros factores explicativos del cambio estructural específicos del sector del aceite de oliva, como son las transformaciones en el marco normativo de la política oleícola y la tendencia al alza tanto de la oferta como de la demanda a nivel mundial. El objetivo del presente trabajo es efectuar una reflexión, desde una perspectiva de demanda, sobre las nuevas coordenadas donde se sitúan las estrategias empresariales de comercialización del aceite de oliva a escala internacional, en un contexto de potencial ampliación de mercados. Se abordan, en primer lugar, los condicionantes de carácter macroeconómico de la comercialización del aceite de oliva en el exterior y, en segundo término, se efectúa el análisis de una serie de factores microeconómicos que configuran las estrategias de los agentes empresariales con respecto a la comercialización del producto., [FR] Un trait caractéristique de l’évolution du secteur de l’huile d’olive réside dans le faible niveau d’internationalisation de ses échanges commerciaux, axés traditionnellement et presque exclusivement dans le cadre des seuls pays producteurs. Ces dernières années ont vu toutefois se dessiner un nouveau scénario de référence pour les agents économiques qui opèrent dans le secteur: d’une part, les tendances dans le sens d’une libéralisation progressive du commerce international, qui contribuent à la mise en place d’un processus de globalisation des échanges internationaux du produit; et, d’autre part, les stratégies des entreprises productrices, qui sont fonction de plus en plus d’une chaîne agroalimentaire décidément basée sur la demande. Mis à part ces prémisses, qui sont généralisables à l’ensemble du système agroalimentaire, il existe un certain nombre d’autres facteurs susceptibles d’expliquer le changement structurel spécifique qu’a connu le secteur de l’huile d’olive, notamment les transformations dans le cadre réglementaire de la politique oléicole et la tendance à la hausse tant de l’offre que de la demande à l’échelle mondiale. Le présent travail a pour objet d’engager une réflexion, dans le cadre de la demande, sur les nouvelles coordonnées susceptibles de délimiter les stratégies d’entreprise de commercialisation de l’huile d’olive à l’échelle internationale, dans un contexte d’élargissement potentiel des marchés. Sont abordés en premier les déterminants macroéconomiques de la commercialisation de l’huile d’olive à l’extérieur, pour envisager ensuite l’analyse d’un certain nombre de facteurs microéconomiques susceptibles de configurer les stratégies d’entreprise des agents producteurs sur le plan de la commercialisation du produit., [EN] A characteristic trait of the development of the olive oil sector was the low internationalisation of trade, which was traditionally concentrated almost exclusively within the producer countries. However, a new reference scenario has taken shape recently for the economic agents operating in the sector: on the one hand, the trends towards a gradual deregulation of international trade are contributing to an emerging process of globalisation of international trade in the product; on the other, the strategies of the business agents are being increasingly influenced by the more demand-oriented agrofood chain. Apart from these premises, which can be generalised to the entire agrofood system, there are other factors that explain the structural change particular to the olive oil sector, such as changes in the system of oil policy regulations and the upward trend of both world-wide supply and demand. This paper seeks to reflect on the new coordinates of the business strategies in the international olive oil trade in a setting of potential market extension, from the demand perspective. Firstly, the macroeconomic factors of the foreign olive oil trade are addressed and, secondly, a series of microeconomic factors, shaping the strategies of the business agents with regard to product trading, are analysed., Commerce international, consommation, distribution, industrie de l’huile d’olive, stratégies d’entreprise, qualité. Globalisation, international trade, consumption, distribution, olive oil industry, business strategies, quality.